1. Field of the Invention
The present invention relates generally to a recording/reproducing apparatus including an auto changer for a disk-like recording medium such as a compact disk, and more particularly to a recording/reproducing apparatus including an auto changer which provides a single record/reproduce means commonly used among a plurality of tray stockers, thereby constituting the recording/reproducing apparatus compact, light, simple, and cheaper.
2. Description of the Prior Art
As disclosed in Unexamined Japanese Utility Model Application No. 4-26461/1992, there is already proposed a reproducing apparatus which stores a plurality of disks and reproduces these disks selectively and successively. Also, disclosed in Unexamined Japanese Patent Application No. 4-74349/1992 is a reproducing apparatus equipped with a rotary disk stocker. FIGS. 1, 2(A), 2(B), and 3 show schematic constructions of these prior arts.
FIG. 1 shows a conventional apparatus using an insertion-type magazine. As shown by alternate long and short dash lines in the drawing, a selected disk 601 is placed in a recessed portion on a tray 602. This tray 602 is inserted into a magazine case 603 in a horizontal direction. Thereafter, the magazine case 603 is installed into a reproducing apparatus 604. The reproducing apparatus 604 extracts the selected tray 602 from the magazine case 603 and places the disk 601 in position for reproduction.
A disadvantage of this insertion-type magazine is that the magazine case 603 needs to be pulled out of the reproducing apparatus 604 every time when the disk 601 is exchanged. Furthermore, as the magazine case 603 is detachable from the reproducing apparatus 604, it is feared that the magazine case 603 may be lost.
FIGS. 2(A) and 2(B) show another conventional apparatus using a rotary-type disk stocker. In the drawings, a reproducing apparatus 610 accommodates a tray stocker 612 therein. This tray stocker 612, having multistage guide grooves each storing a tray 611, is hingedly supported by its support shaft so as to cause a horizontal rotation of approximately 90 degrees. As shown in FIG. 2(A), a disk is loaded on the tray 611 and the tray 611 is inserted into the tray stocker 612. Then, as shown in FIG. 2(B), the tray stocker 612 is rotated 90 degrees in a counterclockwise direction. Subsequently, the reproducing apparatus 610 extracts the tray 611 from the tray stocker 612 and places the selected disk in position for reproduction.
This rotary-type tray stocker is disadvantageous in that a rotation mechanism is specially required. Moreover, the tray stocker 612 needs to be rotated every time when the disk is exchanged. Thus, the exchange operation will be time consuming. Frequent rotations imposed on the rotation mechanism will result in a damage of rotation mechanism. If the rotation mechanism is enlarged for reinforcement, it will become impossible to reduce the size of the reproducing apparatus. Still further, if required to increase the number of disks to be stored, the height of the tray stocker 612 needs to be proportionally increased. Accordingly, the size of the reproducing apparatus 610 will be increased more.
FIG. 3 shows a conventional extraction claw used for extracting a tray 602 (or 611) from the magazine case 603 (or tray stocker 612). As shown in FIG. 3, the claw 620 is engaged with a cutout 621 formed at a front or rear end of the tray 602 (611). This conventional claw 620 is inferior in that a bending moment is generated as shown by an arrow 1. If required to improve flexural, it will be required to increase the thickness of this conventional claw 620 much more.
Furthermore, there is proposed an auto player which is provided with a door for closing and opening for operating disks (i.e. trays). The capacity of the tray stocker is so limited that it will be normally difficult to store all the disks (i.e. trays) in the tray stocker. For this reason, it will be necessary to pull out a non-desired disk from the tray stocker to replace it by a desired disk. In such a case, if a reproduction of other disk is not finished yet, it will be necessary to wait the completion of the reproduction of other disk or forcibly interrupt
In such a reproducing apparatus there is generally provided a fail-safe mechanism for preventing a disk (i.e. tray) from being mistakenly extracted or inserted, wherein the door is entirely locked to protect the apparatus against a user as long as reproduction of a disk is progressing. If the reproduction is once interrupted by opening the door, it will never resume unless the door is again closed.
Especially, in an auto player equipped with a tray stocker, a disk having been reproduced must be returned to the same guide groove of the tray stocker. Therefore, it is strictly prohibited to open the door during the reproduction so that any other disk (i.e. tray) is not inserted into the empty guide groove which is the original guide groove of the presently reproduced disk.
In general, an auto player capable of performing an automatic reproduction by successively selecting a recording medium such as a compact disk comprises a tray stocker having multistage guide grooves storing numerous disks, a mechanism for recording/reproducing of the disk, and a lifter for receiving and returning a tray from and to the tray stocker and further transporting the disk to the recording/reproducing mechanism.
The transporting movement of the lifter is controlled by a drive mechanism including reduction gears and a timing belt. Although using the reduction gears is advantageous in holding the lifter at a constant height against weight of the lifter, the moving speed of the lifter becomes slow. As a need of expanding the capacity of the tray stocker increases, the height of the tray stocker increases proportionally. Meanwhile, there is an earnest need of shortening an access time. In this respect, using the reduction gears is not suitable for satisfying these needs.
When a disk is transferred between the tray stocker and the lifter, the lifter tends to cause a displacement by receive vibration. Thus, undesirable force may be imparted on the disk or others. In order to solve this kind of problem and realize a high-speed lifter, a conventionally adopted means is a balance mechanism which brings an appropriate balance with respect to the weight of the lifter. This conventional balance mechanism normally requires a guide rail disposed in an up-and-down direction and a deadweight sliding along the guide rail. Such a deadweight, however, increases an overall weight and height of the auto player. Furthermore, a fixing means may be required for preventing the lifter from moving during the insertion and pulling out of the disk. As a result, the apparatus will become complicated more and the production cost will increase correspondingly.